
/*
 * Copyright (C) Igor Sysoev
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_SLAB_H_INCLUDED_
#define _NGX_SLAB_H_INCLUDED_


#include <ngx_config.h>
#include <ngx_core.h>


typedef struct ngx_slab_page_s ngx_slab_page_t;

struct ngx_slab_page_s
{
    uintptr_t        slab;
    ngx_slab_page_t *next;
    uintptr_t        prev;
};


typedef struct
{
    ngx_uint_t total;
    ngx_uint_t used;

    ngx_uint_t reqs;
    ngx_uint_t fails;
} ngx_slab_stat_t;


typedef struct
{
    ngx_shmtx_sh_t lock;

    size_t min_size;
    size_t min_shift;

    ngx_slab_page_t *pages;
    ngx_slab_page_t *last;
    ngx_slab_page_t  free;

    ngx_slab_stat_t *stats;
    ngx_uint_t       pfree;

    u_char *start;
    u_char *end;

    ngx_shmtx_t mutex;

    u_char *log_ctx;
    u_char  zero;

    unsigned log_nomem : 1;

    void *data;
    void *addr;
} ngx_slab_pool_t;


void  ngx_slab_sizes_init(void);
void  ngx_slab_init(ngx_slab_pool_t *pool);
void *ngx_slab_alloc(ngx_slab_pool_t *pool, size_t size);
void *ngx_slab_alloc_locked(ngx_slab_pool_t *pool, size_t size);
void *ngx_slab_calloc(ngx_slab_pool_t *pool, size_t size);
void *ngx_slab_calloc_locked(ngx_slab_pool_t *pool, size_t size);
void  ngx_slab_free(ngx_slab_pool_t *pool, void *p);
void  ngx_slab_free_locked(ngx_slab_pool_t *pool, void *p);


#endif /* _NGX_SLAB_H_INCLUDED_ */
